I have built a Weener Wah and want to add more mods.
I would like to be able to adjust the filter as much as possible
I have a rotary for the different center frequencies..
Is an external pot for adjusting the Q of the filter practical? (R7)
Maybe another rotary?
How would you wire an additional pot in series to the main pot?
+ - wiper...hmm..
Where is there more information I could peruse?
Any help is greatly appreciated !
External pot for Q - totally doable. Generally you want a resistor in series with the pot because lower resistance might not give you a workable Q for a wah.
I'm not sure why you would put a pot in series with the main pot, I would think it would really mess up your sweep.
Check out Sabro Tone's wah schematic.
http://www.sabrotone.com/?p=783 (http://www.sabrotone.com/?p=783)
I heard R2 on that schematic can change the mids tone, haven't tried it yet myself.
Good luck!
I recently built a wah with basically all the mods i found on the internet.
The most useful mod in my opinion is the frequency switch which you already have.
After that the gain mod is pretty good. Change r4 to a 1k pot. The signal starts to distort a bit and adds more bass into the signal.
I also made r5 a pot. If I remember a 2k pot with a 1k resistor in series. Adds or takes out a bit of midrange and changes the sweep a bit. Check out the electrosmash article for the frequency plot (link below)
I did the q mod which is changing r7 for a pot and honestly I hear no difference at all. Easy enough to socket r7 and try other resistor values or temporarily put a pot there to see if it makes a difference for you. It could just be the gear that I use. Again check out the frequency response in the electrosmash article
I also tried a pot in series with the rocker pot. I saw it on some schematic somewhere, maybe a version of the dimebag darrel wah so I tried it. I think a 5k pot. It basically acts as a tone knob. Like switching which knotches you use on the rocker. It is basically made irrelevant with the frequency switch.
Maybe you've already read these but they are a great read for anyone who wants to mod a wah. http://www.geofex.com/article_folders/wahpedl/wahped.htm https://www.electrosmash.com/crybaby-gcb-95
Edit. The schematic with the 5k pot in series labeled fine tune. http://www.aronnelson.com/gallery/main.php/v/WAH-ARCHIVE_/WAH-SCHEMATICS/Dunlop_Dimebag_wah.jpg.html?g2_imageViewsIndex=1
Thank you!
Perfect info and advice.